I’m not a biologist or a physicist…or any other ist come to think. But I can tell you an awful lot about the practical effects of this: dE - TdS + pdV \le 0. on what we eat. 
The theory of the ORIGIN OF THE SPECIES and evolution by natural selection is rather simple, although earth shattering I think. First of all it does not speak to the origins of life or the origins of the universe as some would like to suggest. It speaks only to how variability of types of species came about and continues to do so.
It says that any biological system (on earth to be most accurate) in the process of duplicating will and does develop small errors in the code…think of them as typos. The key is that our dna does not duplicate (replicate) itself like a photocopy machine but more like the old days of re-writing each letter by hand. But even in a copy machine as you make successive generations of copies (copy of a copy of a copy) you will lose fidelity. This is what is happening with gene replication, a certain loss of fidelity, or propensity towards mutation.
MOST of this mutation is undesirable and often is weeded out over successive generations.
Occasionally a mutation occurs that allows for an improved ability at survival of a specific sub species. This species will have an environmental advantage and reproduce more of its own than a species less suited to the environment. Example, because there were many short necked giraffes and only a few randomly mutated a longer neck, those with a longer neck could reach an environment of less competition (especially in times of scarcity) so they lived longer and healthier lives passing on code to more children, who in turn had longer necks. Lather, rinse, repeat.
Now here is the part that is hard to accept, though not hard to understand: It normally takes amounts of time our minds just can not fathom. Just like we can fathom the price of a copy machine but the value of Xerox as a company is beyond our experience. Even the slight mutations between the flu virus and the vaccine are very subtle. All the while we have been fighting flu they are still flu virus and we still make a flu vaccine. Though they mutate rather rapidly it is subtle changes and so they remain in the same class of virus.
Over billions of years. Literally billions. This process has shaped the variety of all life we can find today.
So what it shows (with alarming clarity actually) is that over billions of years through 1. faulty replication and 2. environmental pressure all variety of species has adapted out of original single cell life.
The time part is what fools everybody. Keep in mind that in 100,000 years there have been 1388 generations of humans at current life span. That means in one family line there are nearly 1500 generations in 100,000 years. in a family line over a billion years there are hundreds of millions of generations.
It is an abstract to our minds. The number is beyond our reconing.
